The TeraStation has four Western Digital 250 GB hard disks (WDC WD2500BB-22GUC0) on four IDE buses of a IT8212 type controller. Each disk is partitioned approximately like this:

partition 1, 400 MB, RAID auto-detect

partition 2, 120 MB, Swap

partition 3, rest of disk, RAID auto-detect

partition 4, 200 MB, RAID auto-detect

The hd*1 partitions are joined via RAID-1 to make the 400 MB root filesystem.

In the RAID-5 layout, The hd*3 partitions are joined via RAID-5 to make the 700 GB RAID space.

The use of the hd*4 partitions is currently unknown. Maybe there is an emergency system stored there.

The hd*2 partitions are activated as individual swap spaces during boot. There is a potential problem here; should one of the disks die while in use, the whole system is likely to crash because of inaccessable swap space.